Search Results (788)

The aim of this study was to synthesize, characterize, and investigate the biomedical effects of nanoscale cerium phosphate obtained via different synthesis techniques, as well as to evaluate the influence of various CePO₄ concentrations on cells involved in skin structure regeneration (human mesenchymal stem cells, keratinocytes, and fibroblasts) and establish their antioxidant properties. Methods and Results: Cerium(III) orthophosphate was obtained by precipitation with ammonium dihydrogen phosphate from a nitrate solution. By changing the initial concentrations of the solutions and the drying and annealing temperatures, the best conditions for obtaining nanosized phosphate powders were established. The structure of rhabdophane was obtained by X-ray diffraction analysis, and the particle sizes were measured by transmission electron microscopy. The particle sizes ranged from 2 to 10 nm in the transverse direction and 20 to 50 nm in the longitudinal direction. Studies on cell lines have shown a high level of safety, as well as the regenerative potential of CePO₄ nanoparticles, which have a stimulating effect on the proliferation of MSCs at concentrations of 10⁻² to 10⁻³ M for 48 h after application and stimulate the metabolism of human keratinocytes and fibroblasts at a wide range of concentrations (10⁻³ to 10⁻⁵ M). A dose-dependent antioxidant effect of small CePO₄ nanoparticles at a concentration of 10⁻² to 10⁻⁵ has been established, which is stronger than ascorbic acid. Conclusions: A method for obtaining cerium phosphate nanoparticles with beneficial biomedical effects was developed. The non-cytotoxicity and regenerative potential of CePO₄ were established at a wide range of concentrations on different cell lines that are involved in the healing of skin wounds, as were their antioxidant properties. Full article

Most studies on microplastic pollution in aquatic ecosystems have focused on the quantitative and qualitative assessment of particles in surface waters. However, the highest concentrations and accumulation of microplastic particles are observed in bottom sediments. The aim of this study was to determine the concentrations of microplastic particles of different morphology in sediments in the beach and littoral zones of Lake Baikal. This study is the first in relation to Lake Baikal to focus specifically on the analysis of microplastic particles in bottom sediments. The results of the study showed that the registered values of concentration of microplastic particles do not exceed the average values for lakes around the world. The predominant type of particles in both the littoral zone and the beach is microplastic fibers. An exception is observed only for one of the locations. This exception is related to the permanent mooring of vessels in this place. Analysis of the types of artificial polymers showed that the microplastic fibers were represented by polyester, and the fragments were represented by alkyd resin (66%), polyvinyl alcohol (32%) and polyvinyl chloride (2%). Shown for the first time in this study, the presence of large numbers of microplastic particles with rare types of artificial polymers suggests that these particles may be under-reported in other studies. The underestimation of particles may be due either to the selection of sampling locations located far from heavily contaminated areas, or to the fragility of these polymers. Although the harm of these types of polymers has not yet been confirmed, the large number of these particles in local areas of lakes should be taken into account. This is due to the large number of organisms, which is usually characteristic of littoral areas, including Lake Baikal, with its diversity of fauna and flora. Full article

Few studies provide insights on how to incorporate community members’ perspectives of genomic research during the early phases of study development. Engaging with community members early and consistently throughout the research lifecycle could help identify and mitigate barriers to genomic research participation, particularly among groups with rare and understudied cancers. Methods: The Washington University Participant Engagement and Cancer Genome Sequencing (WU-PE-CGS) study formed a Participant Engagement Advisory Board (PEAB) consisting of patients, patient advocates, and patient advocacy organizations who represented the three understudied cancer populations: cholangiocarcinoma, early-onset colorectal cancer in Black Americans, and multiple myeloma in Black Americans. PEAB members were involved in PE-CGS from the time of the grant submission and provided input on key study procedures by participating in monthly project meetings and serving on the leadership team. PEAB recommendations are described in this process paper. Results: The PEAB provided key feedback on recruitment, consent, and survey development. Recruitment optimization focused on making the script more concise, tailoring to participant’s locale, and providing clearer participation expectations. Consent improvements prioritized key information, addressed data protection, and clarified the process of returning genetic results. Survey enhancements included refining scientific terminology and ensuring inclusivity across the cancer continuum. Conclusions: The PEAB provided valuable feedback that improved the development and implementation of WU-PE-CGS research processes. Incorporating the PEAB’s suggestions helped ensure that patients with rare and understudied cancers were successfully enrolled into the WU-PE-CGS. The PEAB will continue to contribute throughout all study phases. Full article

Soil contamination in industrial areas often involves complex mixtures of contaminants, making remediation a significant challenge. Microbe-assisted phytoremediation offers a promising solution, yet its success depends on understanding interaction between plants, microorganisms, and contaminants in rhizosphere. This study examined the effects of organic (oil sludge) and inorganic (Zn) contaminants, applied individually and in combination, on the rhizosphere bacterial community of Miscanthus × giganteus Greef et Deu (M×g), with emphasis on strains exhibiting plant growth-promoting, hydrocarbon-degrading, and metal-tolerant traits. A one-season greenhouse experiment included soils spiked with Zn (1650 mg kg⁻¹) and/or oil sludge (15 mL kg⁻¹). Oil sludge exerted a stronger influence on the taxonomic structure of rhizobacterial communities than Zn, largely shaping the patterns observed under co-contamination. Zn exposure increased the relative abundance of Actinobacteriota, whereas oil sludge favoured Proteobacteriota. Both contaminants, individually and together, enhanced the proportion of Sphingomonadaceae. Across all treatments, taxa with potential plant-growth-promoting traits were present, while co-contaminated soil harboured microorganisms capable of hydrocarbon degradation, heavy metal tolerance, and plant growth promotion. These findings highlight the adaptive capacity of the M×g rhizobiome and support its application in phytoremediation. The isolation and characterisation of rhizosphere-associated strains provide basis for developing microbial bioagents to enhance biomass production and remediation efficiency in multi-contaminated environments. Full article

High-temperature corrosion is a frequently observed phenomenon in waste incineration facilities. Municipal solid waste presents substantial corrosion potential attributed to elevated chlorine content and significant inhomogeneity in calorific value and chemical composition, rendering stable plant operation and corrosion control challenging. Conventional countermeasures, such as cladding or reduced steam parameters, lack temporal resolution and incur substantial costs or reduced efficiency. For this study, a waste incineration plant was equipped with an online corrosion monitoring system featuring ten sensors distributed across three vertical boiler passes. The system employs an electrochemical measurement principle to enable the detection of corrosion with temporal resolution. The recorded data reveals decreasing corrosion attack and increasingly stable deposits along the flue gas path. Combined with the temperature measurements, the sensor data proves the effectiveness of the shower cleaning in the third pass and confirms successful removal of the deposits. Statistical analysis shows a correlation between CO content and sensor data, while other parameters (e.g., steam flow, flue gas temperatures) exhibit no conclusive correlations, emphasizing the system’s added value. Chemical analysis of the electrodes and deposits reveal significant indications of chlorine and sulfur, suggesting chlorine-catalyzed active oxidation as the predominant corrosion mechanism. Full article

Understanding habitat use in sympatric species is key to informing conservation efforts. Lontra felina and L. provocax are semi-aquatic mustelids commonly known as South American marine and southern river otters, respectively, that occupy contrasting coastal environments in southern Chile. We investigated habitat characteristics associated with sightings of both species in the Raúl Marín Balmaceda Multiple Use Protected Area, northern Chilean Patagonia. Our results show L. felina is restricted to exposed, steep rocky shores with sparse vegetation and intertidal belts dominated by Durvillaea antarctica and Lessonia spp., while L. provocax was found to be associated with sheltered, forested margins and estuarine areas dominated by Macrocystis pyrifera and other meadow-forming algae. Records did not show coexistence of both species in the same location; therefore, it is concluded that they exhibit a sympatric but non-syntopic pattern. Full article

We extend the Quantum Memory Matrix (QMM) framework—previously shown to unify gauge interactions and reproduce cold dark matter phenomenology—to account for the observed late-time cosmic acceleration. In QMM, each Planck-scale cell carries a finite-dimensional Hilbert space of quantum imprints. We show that (1) once local unitary evolution saturates the available micro-states, a uniform residual “vacuum-imprint energy” remains; its stress–energy tensor is of pure cosmological-constant form, with magnitude suppressed by the cell capacity, naturally yielding ${\rho }_{\mathrm{\Lambda }}\simeq {(2\times {10}^{-3}\mathrm{eV})}^4$; and (2) if imprint writes continue but are overdamped by cosmic expansion, the coarse-grained entropy field $S\left(t\right)$ undergoes slow-roll evolution, generating an effective equation of state $w\left(z\right)\approx -1+\mathcal{O}\left({10}^{-2}\right)$ that is testable by DESI, Euclid, and Roman. We derive the modified Friedmann equations, linear perturbations, and joint constraints from Planck 2018, BAO, and Pantheon +, finding that the QMM imprint model reproduces the observed TT, TE, and EE spectra without introducing additional free parameters and alleviates the $H_0$ tension while remaining consistent with the large-scale structure. In this picture, dark matter and dark energy arise as gradient-dominated and potential-dominated limits of the same underlying information field, completing the QMM cosmological sector with predictive power and internal consistency. Full article

Cutaneous T-cell Lymphomas (CTCLs) are a heterogeneous group of non-Hodgkin lymphomas that currently have an incompletely understood pathophysiology and several challenges in both diagnosis and management. Single-cell RNA sequencing (scRNA-seq) is a powerful tool that enables the analysis of gene expression at the individual-cell level, revealing cellular heterogeneity and a complex tumor microenvironment. As single-cell RNA sequencing has become increasingly utilized, we aimed to provide an update on recent notable applications of single-cell RNA sequencing in CTCL and their findings. The included studies highlight the intricate network of interactions in the tumor microenvironment that contributes to tumorigenesis. While CTCL is notoriously heterogeneous, our results identify key markers that prove promising for diagnosis, prognostication, and therapeutic targets. Full article

Olive groves (Olea europaea L.) are highly susceptible to soil degradation, particularly water erosion, due to sparse canopy cover and wide inter-row spacing. This study evaluated the effect of different vegetation cover management practices on soil quality and erosion control in a tropical olive grove in southeastern Brazil. The experiment followed a randomized block design with five treatments: exposed soil (BS), olive trees on exposed soil (OB), olive trees with spontaneous vegetation managed with herbicide (OVH), with mowing (OVM), and with mowing + localized weeding (OVMC). Physical, chemical, and biological indicators and losses due to water erosion were analyzed. The OVM and OVMC treatments promoted an increase in soil organic matter (up to 39 g kg⁻¹), microbial biomass carbon (40% higher than BS), enzymatic activity, and glomalin, improving aggregate stability (WMD of 4.9 mm) and reducing soil and water losses by more than 99% compared to exposed soil. The BS and OB treatments, on the other hand, showed higher acidity, lower microbial activity, and greater susceptibility to erosion. The study reinforces that maintaining vegetation cover improves soil quality, mitigates erosion, and promotes the sustainability of olive groves in tropical regions. Full article

The article is devoted to the analysis of changes in the structure of the territory of Kazan in the period from the 18th century to the present. The spatial and temporal variability of the main functional zones of the city is considered. The main ways of expanding the territory of the city and its constituent functional zones related to the main historical processes are given. The total area of the city, according to cartographic analysis, increased 77.04 times in the period from 1739 to 2021. The article presents the dynamics of changes in the areas of the functional zones of the city during the period under review. The characteristic of ecosystems for the biodiversity of terrestrial vertebrates of the identified functional zones is given. Full article

Light pollution is becoming more widespread every year, accompanied by the active use of LED lighting. Currently, the ability of organisms to adapt to this pollution and the potential impact of LED lighting of different color temperatures and intensities on organisms remains poorly understood. In this study, we aimed to find out how long-term light pollution affects the behavior of amphipods Gammarus lacustris, and to compare their locomotor activity under different lighting conditions, taking into account the factor of shelter from light. The response of individuals was compared in group and individual experiments under daylight, without light, warm and cold LED light up to 30 lx. The individuals were from two populations: the first is not exposed to light pollution (lake No. 14), while the second is affected (the Angara River within the city of Irkutsk). The locomotor activity of amphipods was assessed in daylight, without light, warm and cold light of 2–2.5 lx and 10–11 lx in the presence and absence of shelters from light. As a result of the experiments, adaptive changes in the reaction of G. lacustris to warm light were identified in individuals from the Angara River. The importance of LED light color temperature and warm light intensity in determining amphipod response to light was also confirmed. It was found that warm and cold light have different effects on the behavior of G. lacustris, and the presence of shelters from light can reduce the negative impact of light pollution in natural conditions. Full article

A pulse generator capable of outputting quasi-square-wave pulses at the hundred-nanosecond scale is designed. With the development of high-power microwaves, the pulse flat-top is required to be more and more stable. However, at the hundred-nanosecond scale, an equal-value pulse-forming network is prone to being affected by stray parameters in the output waveform. To meet this requirement, a Marx generator and an anti-resonant network is used as the pulse boosting component and the pulse modulation component, respectively. Taking advantage of the anti-resonant network’s fewer sections and good modulation effect, the output waveform of the Marx generator is improved. The modulation ability of two-section and three-section modulation networks on waveforms, the output characteristics of two-section modulation networks, and the effect of stray parameters on the modulation network are explored. The experimental results show that both networks were able to achieve a quasi-square waveform of 100 kV on a 50 Ω load. Compared to the two-section network (165 ns pulse width, 41 ns rise time, 54.54% waveform flatness), the proposed three-section network achieves a pulse width of 185 ns with faster rise time (25 ns) and better waveform flatness (63.78%). Both topologies generate 100 kV quasi-square pulses on 50 Ω loads, with the three-section design demonstrating superior waveform control. In the repetition experiment, the pulse power source achieved stable operation at a repetition frequency of 20 Hz, and a quasi-square waveform with an output voltage of 100 kV was obtained. Finally, compared with previous studies, the modulated Marx generator based on an anti-resonant network has better waveform modulation effect and fewer network sections when generating a Square wave pulse of 100–200 ns. Full article

Optical frequency domain reflectometry (OFDR) is one of the key diagnostic tools for fiber optic components and circuits built on them. A low signal-to-noise ratio, resulting from the low intensity of backscattered signals, prevents the correct quantitative description of the medium parameters. Known methods of signal denoising, such as empirical mode decomposition, frequency filtering, and activation function dynamic averaging, make the signal smoother but introduce errors into its dynamic characteristics, changing the intensity of reflection peaks and distorting the backscattering level. We propose a method to reduce OFDR trace noise using elliptical arc fitting (EAF). The obtained results indicate that this algorithm efficiently processes both areas with and without contrasting back reflections, with zero distortion of Fresnel reflection peaks, and with zero attenuation error in regions without Fresnel reflections. At the same time, other methods distort reflection peaks by 14.2–42.6% and shift the correct level of Rayleigh scattering by 27.2–67.3%. Further work will be aimed at increasing the accuracy of the method and testing it with other types of data. Full article

The assessment of microplastics (MPs) in terrestrial ecosystems has garnered increasing global attention due to their accumulation and migration in soils, which may have potential impacts on soil health, biodiversity, and agricultural productivity. However, research on their distribution and interactions in soil remains limited, especially in tropical regions. This study aimed to characterize MPs extracted from tropical soil samples and relate their abundance to soil and terrain attributes under different land uses (forest, grassland, and agriculture). Soil samples were collected from an experimental farm in Lavras, Minas Gerais, Southeastern Brazil, to determine soil physical and chemical attributes and MP abundance in a micro-watershed. These locations were also used to obtain terrain attributes from a digital elevation model and the normalized difference vegetation index (NDVI). The majority of microplastics found in all samples were identified as polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), and vinyl polychloride (PVC). The spatial distribution of MP was rather heterogeneous, with average abundances of 3826, 2553, and 3406 pieces kg⁻¹ under forest, grassland, and agriculture, respectively. MP abundance was positively related to macroporosity and sand content and negatively related to clay content and most chemical attributes. Regarding terrain attributes, MP abundance was negatively correlated with plan curvature, convergence index, and vertical distance to channel network, and positively related to topographic wetness index. These findings indicate that continuous water fluxes at both the landscape and soil surface scales play a key role, suggesting a tendency for higher MP accumulation in lower-lying areas and soils with greater porosity. These conditions promote MP transport and accumulation through surface runoff and facilitate their entry into the soil. Full article

This study investigates the effect of rice husk content (0–60 wt.%) on the thermal, mechanical and rheological properties of polypropylene composites prepared by extrusion and injection molding. A temperature-invariant approach was applied to analyze the viscoelastic properties, allowing the combination of data obtained at different temperatures. The results show that as the husk content increases, the elastic modulus and hardness rise linearly, while the impact strength and elongation at break significantly decrease. Composites with 40–50% filler exhibit a balanced combination of strength and stiffness, as confirmed by the summary data in the table (provide references). The application of the temperature-invariant viscosity method confirmed its effectiveness in evaluating the flow properties of composite melts. The obtained results have practical significance for the development of eco-friendly polymer materials with natural fiber fillers. Full article